How to: Change brake fluid by yourself

[neil_b]

Here’s the method I use to change the brake fluid by yourself. I use a pressure bleeder to do this.

My video on how to do this is here: https://youtu.be/Y_nw6yqoOkI

My car is a 2001 Boxster S 986.

I’ve listed the tools I use if you want to buy them here: Tools

You should change you brake fluid at least every 2 years.
Your handbook will tell you what brake fluid your car uses. Most use dot 4 fluid.

If you track your car use you'll need a fluid more suited to this. I’ve used a few different types but my favorite is Castrol SRF. Apart from allowing you to spend longer on the track without your brakes fading the pedal will feel firmer and shouldn’t go mushy like with some other fluids.

Here’s a summary of what we’ll be doing:
a. loosen wheel nuts
b. raise
c. take the wheels off
d. suck out old fluid
e. pressure fill with new fluid
f. bleed caliper
g. pump brakes


Tools:
a) jack
b) stands
c) socket set
d) brake bleeder
e) flare spanner
f) clear hose and bottle
g) penetrating fluid
h) plastic cup or bottle
i) and a turkey baster

Parts:
2 liters of brake fluid


1. First loosen the wheel nuts, raise the car and remove the wheels. If you don't know how to do this you can see my other video https://youtu.be/JDksAkO3eO0

2. Open the bonnet and remove the brake fluid reservoir cap. Brake fluid damages paintwork so in case of any spills cover the areas with a clean towel. Using pliers remove the reservoir filter and using the turkey baster remove the fluid from reservoir. fill with new fluid

3. Your handbook will tell you the fluid capacity of the braking system. For my Boxster its 2 litres so pour 2 litres into the brake bleeder.

4. Connect the bleeder to the reservoir and pump it to build up the pressure to 2bar

5. Next you will have to bleed the brake calipers. Your manual will tell you the order to do this. Generally you start with the one furthest from the reservoir.

For my Boxster the order is rear driver, rear passenger, front passenger, front driver

6. Remove the dust cover from the bleed valve.

7. Now we need to loosen the bleed valve. Find a hex socket of the correct size. It needs to have 6 sides or you risk rounding the nut. 10mm is generally correct. Place on bleed valve and crack loose. Tighten backup gently to stop fluid leaking out. If you have difficulty penetrating fluid can help. If you have a larger 4 piston or 6 piston caliper like mine you will have two bleed valves. Loosen and gently tighten back both

8. Put the hose in the bottle and connect to the bleed valve. Using a flare spanner release the bleed nut so fluid starts to come out. It’s important to use a flared spanner or you risk rounding the nut. If you have two bleed valves start with one furthest the brake line.

9. To help get old fluid out of the master cylinder get in the car and push the brake pedal to the floor. Hold it there for 10 seconds then release slowly.

10. Go back to the caliper and when you see fresh clear fluid through the tube and there are no more air bubbles close the bleed valve with the spanner.

If you have two valves then repeat the process. You only need to let a little fluid out as you are only bleeding the short path of the other caliper.

11. Check the pressure on the bleeder and top up to2 bar.
12. Repeat the bleed process on the other 3 calipers in the correct order.
13. Keep an eye on the fluid reservoir as if it runs dry you'll put air in the system.

14. Press the air release button on the brake bleeder to release the pressure Then remove the connection to the fluid reservoir. Using the other bottle top up to the max line if needed the and put the cap back on tight.

15. Check the brake pedal is firm and if so put the wheels back on and lower the car.

16. Test drive the car slowly and check the brakes work.

It’s an idea to keep an eye on the brake fluid level in the reservoir. If it goes down you’ll have a small leak on one of the bleed valves.

As always, please dispose of the used fluid responsibly by taking it to your local council recycling centre.

If you’ve liked these videos then I have more on my Youtube channel https://www.youtube.com/channel/UCCk1LXyP9fJ8jUFbBeaznCw

[JFP in PA]

Originally Posted by neil_b

Here’s the method I use to change the brake fluid by yourself. I use a pressure bleeder to do this.

My video on how to do this is here: https://youtu.be/Y_nw6yqoOkI

My car is a 2001 Boxster S 986.

I’ve listed the tools I use if you want to buy them here: Tools

You should change you brake fluid at least every 2 years.
Your handbook will tell you what brake fluid your car uses. Most use dot 4 fluid.

If you track your car use you'll need a fluid more suited to this. I’ve used a few different types but my favorite is Castrol SRF. Apart from allowing you to spend longer on the track without your brakes fading the pedal will feel firmer and shouldn’t go mushy like with some other fluids.

Here’s a summary of what we’ll be doing:
a. loosen wheel nuts
b. raise
c. take the wheels off
d. suck out old fluid
e. pressure fill with new fluid
f. bleed caliper
g. pump brakes


Tools:
a) jack
b) stands
c) socket set
d) brake bleeder
e) flare spanner
f) clear hose and bottle
g) penetrating fluid
h) plastic cup or bottle
i) and a turkey baster

Parts:
2 liters of brake fluid


1. First loosen the wheel nuts, raise the car and remove the wheels. If you don't know how to do this you can see my other video https://youtu.be/JDksAkO3eO0

2. Open the bonnet and remove the brake fluid reservoir cap. Brake fluid damages paintwork so in case of any spills cover the areas with a clean towel. Using pliers remove the reservoir filter and using the turkey baster remove the fluid from reservoir. fill with new fluid

3. Your handbook will tell you the fluid capacity of the braking system. For my Boxster its 2 litres so pour 2 litres into the brake bleeder.

4. Connect the bleeder to the reservoir and pump it to build up the pressure to 2bar

5. Next you will have to bleed the brake calipers. Your manual will tell you the order to do this. Generally you start with the one furthest from the reservoir.

For my Boxster the order is rear driver, rear passenger, front passenger, front driver

6. Remove the dust cover from the bleed valve.

7. Now we need to loosen the bleed valve. Find a hex socket of the correct size. It needs to have 6 sides or you risk rounding the nut. 10mm is generally correct. Place on bleed valve and crack loose. Tighten backup gently to stop fluid leaking out. If you have difficulty penetrating fluid can help. If you have a larger 4 piston or 6 piston caliper like mine you will have two bleed valves. Loosen and gently tighten back both

8. Put the hose in the bottle and connect to the bleed valve. Using a flare spanner release the bleed nut so fluid starts to come out. It’s important to use a flared spanner or you risk rounding the nut. If you have two bleed valves start with one furthest the brake line.

9. To help get old fluid out of the master cylinder get in the car and push the brake pedal to the floor. Hold it there for 10 seconds then release slowly.

10. Go back to the caliper and when you see fresh clear fluid through the tube and there are no more air bubbles close the bleed valve with the spanner.

If you have two valves then repeat the process. You only need to let a little fluid out as you are only bleeding the short path of the other caliper.

11. Check the pressure on the bleeder and top up to2 bar.
12. Repeat the bleed process on the other 3 calipers in the correct order.
13. Keep an eye on the fluid reservoir as if it runs dry you'll put air in the system.

14. Press the air release button on the brake bleeder to release the pressure Then remove the connection to the fluid reservoir. Using the other bottle top up to the max line if needed the and put the cap back on tight.

15. Check the brake pedal is firm and if so put the wheels back on and lower the car.

16. Test drive the car slowly and check the brakes work.

It’s an idea to keep an eye on the brake fluid level in the reservoir. If it goes down you’ll have a small leak on one of the bleed valves.

As always, please dispose of the used fluid responsibly by taking it to your local council recycling centre.

If you’ve liked these videos then I have more on my Youtube channel https://www.youtube.com/channel/UCCk1LXyP9fJ8jUFbBeaznCw

With the exception of using a turkey baster and siphoning out the existing fluid, not a bad write up.

When using a pressure system like the Motive system, siphoning out the old fluid is completely unnecessary, and is usually the place where most first time DIY jobs go wrong when the baster drips bake fluid all over the place, usually running some paint. The Motive tool uses positive displacement to push out all the old fluid, so removing what is in the reservoir before hand is actually a waste of time.

[JayG]

What braking system do you have? IIRC, the boxster uses less than 1 liter for a full flush
Also Castrol RBF is major overkill for most people, its 2 to 4 times the cost of ATE 200 or Motul RBF 600

For proper drive cars (left hand), you bleed the rear passenger, then driver, then front passenger, then driver

All Boxsters use DOT 4 fluid and have at least 4 piston calipers with inside and outside bleeders


Nice write up

[neil_b]

Braking system? I don't have PSM if that's what you mean?

Only 1 liter? That's good to hear. I just say 2 liters because that's what the Bentley manual advises but you could be right that it's less in practice.

Yes, I agree totally. Castrol SRF is really expensive and overkill for everyday driving. I thought I said this in the video though?

Should probably have said that my car is UK spec so the brake fluid reservoir is probably on the other side to US cars. I'd be interested to know if this changes the order you need to bleed. I've just done it in the order the Bentley manual said and worked fine for me.

[mikesz]

I have a 99 base USA Spec. Changed my fluid when I replaced the waterlogged brake booster. While I was at it I replaced the master cylinder and installed the retro kit to eliminate said water logged brake booster. I just opened up the right rear bleeder valve and let gravity take its course. Thouroghly drained all fluid and replaced bleeder valves with speed bleeders from pelican. While I had the system drained I cleaned and painted my calipers and replaced rotors with drilled rotors.

[Sam7768]

Hello All,

I do not have way to lift all the wheels up at the same time.

My question is, can I bleed the break fluid from the calipers, one wheel at a time (and put the wheel back and then up the second wheel and so on) or will it have any impact on the the break lines due to pressure?

Thanks

Sam

[Racer Boy]

You can do them one at a time, no problem.

[78F350]

Originally Posted by Sam7768

Hello All,

I do not have way to lift all the wheels up at the same time.

My question is, can I bleed the break fluid from the calipers, one wheel at a time (and put the wheel back and then up the second wheel and so on) or will it have any impact on the the break lines due to pressure?

Thanks

Sam

Depending on the wheels you have and the size of your hands, you may not need to lift any of them up. I have flushed my brakes by positioning the car so that I could just reach between the spokes with a wrench and open/close the bleeder.

[JayG]

Originally Posted by 78F350

Depending on the wheels you have and the size of your hands, you may not need to lift any of them up. I have flushed my brakes by positioning the car so that I could just reach between the spokes with a wrench and open/close the bleeder.

Yup, just need to be careful not to drip fluid on the wheels

[robdelorenzo]

Here’s a semi-related dumb question. Since I have rounded up the supplies to replace the rotors & pads on the front, I decided that I may as well paint the calipers while I am at it. I have all new hardware as well. I have only ever replaced pads and never removed a caliper completely. What happens to the fluid after I unscrew the brake line? It’s under pressure, correct? Does it flow out everywhere and let air into the system or do I need to plug the line somehow? I have a Motive Bleeder and new fluid and was planning on flushing the fluid after completing the painting & rotor & pad replacements.
As always, thanks for the help. The people on this board are very helpful!

[robdelorenzo]

Bumped for some help, please.

[maytag]

Originally Posted by robdelorenzo

Bumped for some help, please.

Many people have done a very nice job of painting calipers without actually removing the brake lines from them.
however, if you want to go that route, yes, once you remove the brake line from the caliper, the fluid will slowly dribble out of that brake line. but not under pressure; simple gravity. Sometimes a silicone vacuum cap of the appropriate size can stem the flow while you are painting.
But there is no way around you will have to at very least bleed the system after you reattach them. a full flush is always a good idea when you're there.

Sent from my SM-G970U using Tapatalk

[robdelorenzo]

Thank you Maytag.

[maytag]

Originally Posted by robdelorenzo

Thank you Maytag.

of course! Sorry you had to ping us twice! haha.

Typically this forum is very quick to help, so by the time I see a thread, it's handled. ;-):dance:

[Phat Hippy]

+1
Get multiple sizes of cap/plugs so you can plug the caliper holes also...There is still a lot of fluid in there that will mess up your new paint job. Use some old bleed nipples also, that way you can paint right over them then replace later. Saves some time masking them.

[robdelorenzo]

Indeed.The people on this board are most kind and generous with their knowledge.